achievement gap
"When Steele gave a large group of Stanford sophomores a set of questions from Graduate Record Examination (GRE) and told the students that it would measure their innate intellectual ability, he found that the white students performed significantly better than their black counterparts. [...] However, when Steele gave a separate group of students the same test, but stressed that it was not a measure of intelligence - he told them it was merely a preparatory drill - the scores of the white and black students were virtually identical."
".. the same effect also exists when women take a math test that supposedly measures 'cognitive difference between the genders' or when white males are exposed to a stereotype about the academic superiority of Asians."
"'What you tend to see during stereotype threat is carefulness and second-guessing,' Steele said. 'When you go and interview them, you have the sense that when they are in the stereotype-threat condition they say to themselves, 'Look, I'm going to be careful here, I'm not going to mess things up.' Then, after having decided to take that strategy, they calm down and go through the test. The more you do that, the more you will get away from the intuitions that help you, the quick processing. They think they did well, and they are trying to do well. But they are not.'"
-- from How we decide, by Jonah Lehrer
".. the same effect also exists when women take a math test that supposedly measures 'cognitive difference between the genders' or when white males are exposed to a stereotype about the academic superiority of Asians."
"'What you tend to see during stereotype threat is carefulness and second-guessing,' Steele said. 'When you go and interview them, you have the sense that when they are in the stereotype-threat condition they say to themselves, 'Look, I'm going to be careful here, I'm not going to mess things up.' Then, after having decided to take that strategy, they calm down and go through the test. The more you do that, the more you will get away from the intuitions that help you, the quick processing. They think they did well, and they are trying to do well. But they are not.'"
-- from How we decide, by Jonah Lehrer